This invention relates to improvements in the electrodeposition of zinc from aqueous acidic plating baths, and particularly to new compositions which are useful as additives in plating baths for plating bright and level zinc deposits from aqueous acid plating baths, and more particularly to such baths containing relatively high concentrations of metal.
Considerable attention has been directed over the years to the development of zinc electroplating baths which will produce bright and level zinc deposits of improved quality. Much research has been devoted to improving the overall brightness, the range of allowable current densities, and the ductility of the zinc deposit. Until recently, most of the successful zinc plating baths were aqueous alkaline zinc plating baths containing substantial quantities of cyanide which has caused concern regarding toxicity and waste disposal problems. Accordingly, activity in the plating area has been devoted either to the development of cyanide-free alkaline plating baths or improvements in acid plating baths. This invention relates to acid plating baths.